The dried shellfish products with rich nutrients and low-calorie content are favorite food in China,especially in coastal areas.However,the species of dried shellfish products in the market are usually unknown,as the ...The dried shellfish products with rich nutrients and low-calorie content are favorite food in China,especially in coastal areas.However,the species of dried shellfish products in the market are usually unknown,as the taxonomic features were removed during the production process.This study described the application of DNA barcoding technique to the identification of 100 dried shellfish(scallop,squid,octopus and cuttlefish)products in markets.Samples were authenticated by comparing mitochondrial cytochrome oxidase subunit I(COI)gene and 16S ribosomal RNA(16S rRNA)gene sequences with public reference taxonomic databases.The results showed that all the 100 products can be identified at species level.Sixty four scallop adductor products were processed using the bay scallop,Argopecten irradians,and one was from Portuguese oyster,Crassostrea angulata.All the 27 squid,2 cuttlefish and 6 octopus products were produced by the Jumbo flying squid,Dosidicus gigas.The neighbour-joining tree is in agreement with the results of DNA barcoding analysis.The 64 scallop samples formed one A.irradians cluster,leaving Sca65 clustered with the reference oyster sequence C.angulata(MH997922).All the 35 cephalopod(squid,octopus and cuttlefish)samples formed a D.gigas cluster.This investigation revealed a low variety of dried shellfish products sold on the market,and highlighted the high rate of mislabeling and species substitution.Our present work provides a practical method for tracing and authenticating shellfish products.展开更多
[Objectives]To compare anti-inflammatory and analgesic effects of fresh and dry products of Zhuang medicine Asystaia gangetica on mice.[Methods]Experiments were performed using glacial acetic acid to increase capillar...[Objectives]To compare anti-inflammatory and analgesic effects of fresh and dry products of Zhuang medicine Asystaia gangetica on mice.[Methods]Experiments were performed using glacial acetic acid to increase capillary permeability in mice,cotton ball to cause granulomatous formation in mice,xylene to cause auricular swelling in mice,chronic inflammation,and acetic acid-induced pain and hot-plate pain.Besides,the anti-inflammatory and analgesic effects of fresh and dry products of A.gangetica on mice were observed with the indicators of capillary permeability in the abdominal cavity,swelling rate of auricles,cotton ball granulomas and writhing times,and thermal pain threshold.[Results]Fresh products of A.gangetica had significant inhibitory effects on peritoneal capillary permeability increase in mice induced by glacial acetic acid,mouse auricle swelling induced by xylene,and mouse granuloma formation induced by cotton balls.Dry products of A.gangetica also significantly inhibited the auricle swelling in mice induced by xylene,but the effect intensity was weaker than that of fresh products.In addition,dry products of A.gangetica showed a certain tendency to inhibit the increase of capillary permeability in the abdominal cavity of mice induced by glacial acetic acid.In the analgesic experiment,both fresh and dry products of A.gangetica showed better analgesic effect,but caused pain on the hot plate,and the analgesic effect time of fresh products was shorter than that of dry products.[Conclusions]Both fresh and dry products of Zhuang medicine A.gangetica have certain anti-inflammatory and analgesic effects.展开更多
An energy production system consisting of a solar collector, biogas dry reforming reactor and solid oxide fuel cell (SOFC) was assumed to be installed in Kolkata, India. This study aims to understand the impact of cli...An energy production system consisting of a solar collector, biogas dry reforming reactor and solid oxide fuel cell (SOFC) was assumed to be installed in Kolkata, India. This study aims to understand the impact of climate conditions on the performance of solar collectors with different lengths of parabolic trough solar collector (dx) and mass flow rate of heat transfer fluid (m). In addition, this study has evaluated the amount of H2 produced by biogas dry reforming (GH2), the amount of power generated by SOFC (PSOFC) and the maximum number of possible households (N) whose electricity demand could be met by the energy system proposed, considering the performance of solar collector with the different dx and m. As a result, the optimum dx was found to be 4 m. This study revealed that the temperature of heat transfer fluid (Tfb) decreased with the increase in m. Tfb in March, April and May was higher than that in other months, while Tfb from June to December was the lowest. GH2, PSOFC and N in March, April and May were higher than those in other months, irrespective of m. The optimum m was 0.030 kg/s.展开更多
To clarify the effects of mechanical sowing and transplanting on dry mat- ter production of middle-season hybrid rice, a two-factor split plot design was used to study the effects of different sowing and transplanting...To clarify the effects of mechanical sowing and transplanting on dry mat- ter production of middle-season hybrid rice, a two-factor split plot design was used to study the effects of different sowing and transplanting methods and their interac- tion with the seedling number per hill or seeding time on dry matter accumulation, distribution and transformation of F You 498, a middle-season hybrid rice variety, under field conditions in 2012 and 2013. The results showed that there was a marked effect of the sowing and transplanting methods and their interaction with the seedling number per hill or seeding time on dry matter accumulation, distribution and transformation. The total population dry matter accumulation of the treatments with mechanical direct seeding (MDS) and machine-based transplanting (MT) was lower than that of the treatment with traditional manual transplanting (TMT). How- ever, MDS had higher dry matter accumulation and accumulating rate in the joint- ing-earing stage,and maintained higher stem-sheath exportation, export rate and transformation than MT and TMT; MT had higher dry matter accumulation and ac- cumulating rate in the heading-maturity period than MDS and TMT. Moreover, the treatments with low seedling number per hill or early seeding enhanced the assimi- lation of dry matter after heading,the ratio of dry matter accumulation after earing to biomass yield and the contribution rate of dry matter accumulation after earing, and a reasonable early sowing was favorable to increase the harvest index of middle- season hybrid rice under mechanical sowing and transplanting conditions.展开更多
Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha...Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha, were used as materials to study the dry matter production characteristics. The super hybrid rice showed a high ability in dry matter production and accumulation and its yield enhanced with the increase of dry matter accumulation. The advantage period of dry matter production in the super hybrid rice was mainly at the middle and late growth stages compared with the check. The grain yield had no significant correlation with the dry matter accumulation before the elongation stage while had a significantly positive correlation with the dry matter accumulation from the elongation to maturity stages in super hybrid rice. There were more dry matter in vegetative organs at the heading stage in the super hybrid rice but its contribution to yield (apparent conversion percentage) was averagely 4.3 percent points lower than that in the check. For crop growth rate (CGR), the comparative advantage of super hybrid rice was at the middle and late stages, especially after flowering. Moreover, as the rising of leaf area index (LAI) and leaf area duration (LAD), CGR enhanced. The total LAD and the mean of lAD per day of super hybrid rice was about 14.79% and 10.31% higher than those of the check, respectively. The results indicate that the high yield of super hybrid rice mostly comes from the products of photosynthesis after heading, which is shown by the increased CGR at middle and later stages. It is suggested that LAD character might be used to better explain the advantage in the dry matter production of super hybrid rice than LAI.展开更多
We developed a species-specific PCR method to identify species among dehydrated products of 10 sea cucumber species.Ten reverse species-specific primers designed from the 16 S rRNA gene,in combination with one forward...We developed a species-specific PCR method to identify species among dehydrated products of 10 sea cucumber species.Ten reverse species-specific primers designed from the 16 S rRNA gene,in combination with one forward universal primer,generated PCR fragments of ca.270 bp length for each species.The specificity of the PCR assay was tested with DNA of samples of 21 sea cucumber species.Amplification was observed in specific species only.The species-specific PCR method we developed was successfully applied to authenticate species of commercial products of dehydrated sea cucumber,and was proven to be a useful,rapid,and low-cost technique to identify the origin of the sea cucumber product.展开更多
The dry matter production and its nutrient amounts varied significantly with time and period from April to June was a favourable season for plant growth. Dry matter production declined significantly with clipping. E...The dry matter production and its nutrient amounts varied significantly with time and period from April to June was a favourable season for plant growth. Dry matter production declined significantly with clipping. Especially, repeated cutting of high frequencies for the long term had a severe effect on dry matter production. However, N, P, and K amounts in dry matter production did not significantly decline because the concentrations of N, P, and K in the plants increased with clipping. Repeated cutting for long term is a reason why net primary production has been depressed in the most of upland areas of southern China.展开更多
High-yield rice varieties with a suitable growth duration are required for mechanical transplanting in multiple cropping systems. Daily yield is an appropriate criterion for the selection of machine-transplanted rice ...High-yield rice varieties with a suitable growth duration are required for mechanical transplanting in multiple cropping systems. Daily yield is an appropriate criterion for the selection of machine-transplanted rice varieties. The aim of this study was to investigate the growth characteristics and grain production in machine-transplanted medium indica hybrid rice with a high daily yield. We conducted a field experiment on 20 medium indica hybrid rice varieties in 2017 and 2018.Grain yield decreased significantly with growth duration between jointing and heading, but it increased with dry matter accumulation, growth rate between jointing and heading, dry matter partitioning to the stem plus sheath at heading, daily yield, and number of spikelets per panicle. Compared with the medium and low daily yield variety types, the high daily yield variety type increased shoot biomass by improving crop growth rate and dry matter accumulation amount between jointing and heading and after heading. The high daily yield variety type decreased the growth duration pre-heading and the proportions of dry matter partitioned to the leaf lamina at heading and maturity, but it also increased the post-heading accumulated dry matter in the grain and the remobilization of dry matter stored in the vegetative organs. Furthermore,the high daily yield variety type significantly increased the occurrence rate of tillers, which is beneficial for the formation of a larger panicle size and an increase in the grain-filling rate. These changes contributed to a 6.51–23.16% relative increase in grain yield of the high daily yield variety type. In conclusion, the selection of high daily yield indica hybrid rice varieties with shorter pre-heading growth duration, greater tiller occurrence rate and spikelet numbers per panicle, higher post-jointing growth rates and stem plus sheath dry matter accumulation at heading is suitable for machine-transplanted rice.展开更多
Nitrogen is one of the most important nutrients in rice production but its uptake dynamics remained relatively unexplored. The present investigation evaluated uptake dynamics over the growing season at different level...Nitrogen is one of the most important nutrients in rice production but its uptake dynamics remained relatively unexplored. The present investigation evaluated uptake dynamics over the growing season at different levels of nitrogen fertilizer application. The experiment was conducted during Boro season (November-April) at Bangladesh Rice Research Institute experimental farm, Gazipur, Bangladesh. The experiment involved two modem rice varieties-BRRl dhan28 and BRRI dhan29 and six N rates: 0, 50, 100, 150, 200 and 250 kg·ha^-1. The N uptake pattern was determined at every 15 days from transplanting to maturity. At 150 kg·N·ha^-1, initially N uptake was 0.1 kg.hal.day1 which increased to 0.2 in BRRI dhan28 and 0.4 in BRRI dhan29, respectively. During 30 to 45 DAT, per day N uptake was 2.0 kg-ha1 in BRRI dhan28 and 2.2 in BRRI dhan29 which increased to the peak at 2.4 and 2.8 kg·ha^-1·day^-1 in BRRI dhan28 and BRRI dhan29, respectively, during 45 to 60 DAT. The grain yield showed a stronger correlation with N uptake during 45 to 60 DAT in both the varieties. The highest N uptake contributed to the highest dry matter production in both the varieties.展开更多
Applying mathematic models to evaluate absorbed-N effects on dry matter production at different developmental stages would help determine proper nitrogen management according to crop demands and yield target. Two fiel...Applying mathematic models to evaluate absorbed-N effects on dry matter production at different developmental stages would help determine proper nitrogen management according to crop demands and yield target. Two field trials were carried out for establishing absorbed-N effects on dry matter production(ANEDr) model, using uniform design in 2010–2011and 2012–2013 winter wheat growing seasons in Hebei Province, China. Another field trial was carried out in 2010–2011for model validation. Dry matter and N concentration in leaf and non-leaf organs were measured at setting, jointing, anthesis, and maturity. Theory of best linear unbiased prediction(BLUP) was applied to analyse the N effects of leaf and non-leaf organs on dry matter production. Within ANEDr model, four N-affected phases at each stage were concerned,leaf absorbed-N effect before this stage, non-leaf organ absorbed-N effect before this stage,leaf absorbed-N effect at this stage, and non-leaf organ absorbed-N effect at this stage. In addition, developmental processes, genotype characters and temperature were three factors that determine each N effect. It was demonstrated that ANEDr model can precisely quantify absorbed-N effects on dry matter production with high correlation coefficient(r=0.95). Comparing with other models, ANEDr model considered both leaf and non-leaf organs according to developmental processes of winter wheat, showed higher flexibility and simplicity, thus could be applied to different environments, cultivars and crops after parameter adjustment.展开更多
We studied the characteristics of dry matterproduction and matter partitioning in hybridrice and the relationships of them with heterot-ic effect in 1993. Two popular indica hybrids, Shanyou 63(Zhenshan 97A/Minhui 63 ...We studied the characteristics of dry matterproduction and matter partitioning in hybridrice and the relationships of them with heterot-ic effect in 1993. Two popular indica hybrids, Shanyou 63(Zhenshan 97A/Minhui 63 ) and Teyou 63(Longtepu A/Minhui 63), as well as theircommon restorer line, Minhui 63 (elite cultivar展开更多
Background:The ability to finish livestock on pasture over the summer–autumn period could improve the profitability of red meat enterprises in drought-prone temperate regions.In south-eastern Australia,traditional pe...Background:The ability to finish livestock on pasture over the summer–autumn period could improve the profitability of red meat enterprises in drought-prone temperate regions.In south-eastern Australia,traditional perennial options are limited by poor warm-season performance(phalaris,Phalaris aquatica L.)and widespread environmental constraints(lucerne,Medicago sativa L.).We aimed to identify perennial species suitable for summer–autumn finishing.Methods:We tested pure swards of summer-active perennial grasses and herbs(20 cultivars across 14 species)in replicated small-plot experiments at two sites on the Southern Tablelands of New South Wales,Australia.We assessed early persistence,productivity and warm-season nutritive characteristics over 2–3 years.Results:Lucerne and chicory(Cichorium intybus L.)persisted well through drought and produced herbage of high quantity and quality through summer–autumn.Digit grass(Digitaria eriantha Steud.)was highly persistent and productive but nutritive values were generally poor.Cocksfoot(Dactylis glomerata L.),tall fescue(Festuca arundinacea Schreb.),perennial ryegrass(Lolium perenne L.),prairie grass(Bromus willdenowii Kunth.)and plantain(Plantago lanceolata L.)were productive but less persistent through drought,while nutritive values were sometimes inadequate.Conclusions:Chicory is a good alternative to lucerne,given its excellent summer–autumn performance,ability to survive droughts and superior acid soil tolerance.If appropriate management resolves issues with persistence and nutritive value,several of the other species could also be used to close the warm-season feed gap in drought-prone temperate environments.展开更多
Large quantities of mussel shells (66000-94000 t year^-1), an alkaline material that can be used as a soil amendment, are generated as waste in Galicia, NW Spain. A field trial was carried out by planting different ...Large quantities of mussel shells (66000-94000 t year^-1), an alkaline material that can be used as a soil amendment, are generated as waste in Galicia, NW Spain. A field trial was carried out by planting different pasture species in a Haplic Umbrisol using a randomized block design with four blocks and six treatments (not amended control or soil amended with lime, finely ground shell, coarsely ground shell, finely ground calcined shell or coarsely ground calcined shell) to compare the effects of lime and mussel shells additions on a soil with a low cation exchange capacity and high AI saturation. The trial was established in March 2007, and samples of plants and soil were collected when plots were harvested in summer 2008 (separating the bulk and rhizosphere soil). The soils were analyzed for pH, total C, total N, available P, exchangeable cations, effective cation exchange capacity and available micronutrients. Dry matter yield was measured in all plots and plants were analyzed for nutrients. Application of mussel shells and the commercial lime resulted in an increase in pH and exchangeable Ca and a decrease in exchangeable Al and Al were most noticeable in the rhizosphere. The amendment of Ca in the plant. saturation. The stability of pH over time was high. These effects also had a positive effect on dry matter yield and concentration展开更多
The effects of 0, 2.5, 5.0, and 10.0 pmol/L Cd^2+(Cd(NO3)2.4H2O) and 0, 10, 25, 50, and 100 mmol/L NaCl on growth, photosynthesis and the content of some ions in maize (Zea mays L.) were investigated in the pre...The effects of 0, 2.5, 5.0, and 10.0 pmol/L Cd^2+(Cd(NO3)2.4H2O) and 0, 10, 25, 50, and 100 mmol/L NaCl on growth, photosynthesis and the content of some ions in maize (Zea mays L.) were investigated in the present study. With Increasing concentrations of Cd^2+ or NaCI alone in Hoagland nutrient solution, the chlorophylls and starch content decreased. Combination treatment with salinity and cadmium increased the negative effects observed following the two stresses alone. Plants exhibiting growth retardation in response to one mild stress factor (25-50 mmol/L NaCl) became more tolerant to the other stress factor (Cd). The exposure of plants to cadmium caused a partial reversal of the effects of salinity. Root and shoot growth, ion accumulation and levels of photosynthetic pigments were improved at moderate concentrations of the two stress factors Imposed jointly.展开更多
基金This work was supported by research grants from the Fundamental Research Funds for the Central Universities(No.201762014)the National Natural Science Foundation of China(No.31772414)the National Natural Science Foundation of Qingdao City(No.20-3-4-16-nsh).
文摘The dried shellfish products with rich nutrients and low-calorie content are favorite food in China,especially in coastal areas.However,the species of dried shellfish products in the market are usually unknown,as the taxonomic features were removed during the production process.This study described the application of DNA barcoding technique to the identification of 100 dried shellfish(scallop,squid,octopus and cuttlefish)products in markets.Samples were authenticated by comparing mitochondrial cytochrome oxidase subunit I(COI)gene and 16S ribosomal RNA(16S rRNA)gene sequences with public reference taxonomic databases.The results showed that all the 100 products can be identified at species level.Sixty four scallop adductor products were processed using the bay scallop,Argopecten irradians,and one was from Portuguese oyster,Crassostrea angulata.All the 27 squid,2 cuttlefish and 6 octopus products were produced by the Jumbo flying squid,Dosidicus gigas.The neighbour-joining tree is in agreement with the results of DNA barcoding analysis.The 64 scallop samples formed one A.irradians cluster,leaving Sca65 clustered with the reference oyster sequence C.angulata(MH997922).All the 35 cephalopod(squid,octopus and cuttlefish)samples formed a D.gigas cluster.This investigation revealed a low variety of dried shellfish products sold on the market,and highlighted the high rate of mislabeling and species substitution.Our present work provides a practical method for tracing and authenticating shellfish products.
基金Talent Cultivation Construction Project of Professor Yang Shilin's Team of Guangxi University of Chinese Medicine(CS17015).
文摘[Objectives]To compare anti-inflammatory and analgesic effects of fresh and dry products of Zhuang medicine Asystaia gangetica on mice.[Methods]Experiments were performed using glacial acetic acid to increase capillary permeability in mice,cotton ball to cause granulomatous formation in mice,xylene to cause auricular swelling in mice,chronic inflammation,and acetic acid-induced pain and hot-plate pain.Besides,the anti-inflammatory and analgesic effects of fresh and dry products of A.gangetica on mice were observed with the indicators of capillary permeability in the abdominal cavity,swelling rate of auricles,cotton ball granulomas and writhing times,and thermal pain threshold.[Results]Fresh products of A.gangetica had significant inhibitory effects on peritoneal capillary permeability increase in mice induced by glacial acetic acid,mouse auricle swelling induced by xylene,and mouse granuloma formation induced by cotton balls.Dry products of A.gangetica also significantly inhibited the auricle swelling in mice induced by xylene,but the effect intensity was weaker than that of fresh products.In addition,dry products of A.gangetica showed a certain tendency to inhibit the increase of capillary permeability in the abdominal cavity of mice induced by glacial acetic acid.In the analgesic experiment,both fresh and dry products of A.gangetica showed better analgesic effect,but caused pain on the hot plate,and the analgesic effect time of fresh products was shorter than that of dry products.[Conclusions]Both fresh and dry products of Zhuang medicine A.gangetica have certain anti-inflammatory and analgesic effects.
文摘An energy production system consisting of a solar collector, biogas dry reforming reactor and solid oxide fuel cell (SOFC) was assumed to be installed in Kolkata, India. This study aims to understand the impact of climate conditions on the performance of solar collectors with different lengths of parabolic trough solar collector (dx) and mass flow rate of heat transfer fluid (m). In addition, this study has evaluated the amount of H2 produced by biogas dry reforming (GH2), the amount of power generated by SOFC (PSOFC) and the maximum number of possible households (N) whose electricity demand could be met by the energy system proposed, considering the performance of solar collector with the different dx and m. As a result, the optimum dx was found to be 4 m. This study revealed that the temperature of heat transfer fluid (Tfb) decreased with the increase in m. Tfb in March, April and May was higher than that in other months, while Tfb from June to December was the lowest. GH2, PSOFC and N in March, April and May were higher than those in other months, irrespective of m. The optimum m was 0.030 kg/s.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201303129)National Science and Technology Project for Bump Crop(2011BAD16B05)Scientific Research Foundation of Sichuan Agricultural University~~
文摘To clarify the effects of mechanical sowing and transplanting on dry mat- ter production of middle-season hybrid rice, a two-factor split plot design was used to study the effects of different sowing and transplanting methods and their interac- tion with the seedling number per hill or seeding time on dry matter accumulation, distribution and transformation of F You 498, a middle-season hybrid rice variety, under field conditions in 2012 and 2013. The results showed that there was a marked effect of the sowing and transplanting methods and their interaction with the seedling number per hill or seeding time on dry matter accumulation, distribution and transformation. The total population dry matter accumulation of the treatments with mechanical direct seeding (MDS) and machine-based transplanting (MT) was lower than that of the treatment with traditional manual transplanting (TMT). How- ever, MDS had higher dry matter accumulation and accumulating rate in the joint- ing-earing stage,and maintained higher stem-sheath exportation, export rate and transformation than MT and TMT; MT had higher dry matter accumulation and ac- cumulating rate in the heading-maturity period than MDS and TMT. Moreover, the treatments with low seedling number per hill or early seeding enhanced the assimi- lation of dry matter after heading,the ratio of dry matter accumulation after earing to biomass yield and the contribution rate of dry matter accumulation after earing, and a reasonable early sowing was favorable to increase the harvest index of middle- season hybrid rice under mechanical sowing and transplanting conditions.
基金the State Science and Technology Program of Grain Harvests in China (Grant Nos. 2006BAD02A06 and 2006BAD02A04)
文摘Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha, were used as materials to study the dry matter production characteristics. The super hybrid rice showed a high ability in dry matter production and accumulation and its yield enhanced with the increase of dry matter accumulation. The advantage period of dry matter production in the super hybrid rice was mainly at the middle and late growth stages compared with the check. The grain yield had no significant correlation with the dry matter accumulation before the elongation stage while had a significantly positive correlation with the dry matter accumulation from the elongation to maturity stages in super hybrid rice. There were more dry matter in vegetative organs at the heading stage in the super hybrid rice but its contribution to yield (apparent conversion percentage) was averagely 4.3 percent points lower than that in the check. For crop growth rate (CGR), the comparative advantage of super hybrid rice was at the middle and late stages, especially after flowering. Moreover, as the rising of leaf area index (LAI) and leaf area duration (LAD), CGR enhanced. The total LAD and the mean of lAD per day of super hybrid rice was about 14.79% and 10.31% higher than those of the check, respectively. The results indicate that the high yield of super hybrid rice mostly comes from the products of photosynthesis after heading, which is shown by the increased CGR at middle and later stages. It is suggested that LAD character might be used to better explain the advantage in the dry matter production of super hybrid rice than LAI.
基金Supported by the National Natural Science Foundation of China(No.31201999)the Natural Science Foundation of Guangdong Province,China(No.S2011040000463)+4 种基金the Foundation for Distinguished Young Talents in Higher Education of Guangdong,China(No.LYM11086)the Key Laboratory Program of Tropical Marine Bio-Resources and Ecology,Chinese Academy of Science(No.LMB111004)the China Spark Program(Nos.2012GA780007,2012GA780020,2012GA780008)the National Students'Innovation and Entrepreneurship Training Project(No.201210579031)the Zhanjiang Foundation for Science and Technology,China(Nos.2011C3104009,2011D0244,2012C3102018)
文摘We developed a species-specific PCR method to identify species among dehydrated products of 10 sea cucumber species.Ten reverse species-specific primers designed from the 16 S rRNA gene,in combination with one forward universal primer,generated PCR fragments of ca.270 bp length for each species.The specificity of the PCR assay was tested with DNA of samples of 21 sea cucumber species.Amplification was observed in specific species only.The species-specific PCR method we developed was successfully applied to authenticate species of commercial products of dehydrated sea cucumber,and was proven to be a useful,rapid,and low-cost technique to identify the origin of the sea cucumber product.
文摘The dry matter production and its nutrient amounts varied significantly with time and period from April to June was a favourable season for plant growth. Dry matter production declined significantly with clipping. Especially, repeated cutting of high frequencies for the long term had a severe effect on dry matter production. However, N, P, and K amounts in dry matter production did not significantly decline because the concentrations of N, P, and K in the plants increased with clipping. Repeated cutting for long term is a reason why net primary production has been depressed in the most of upland areas of southern China.
基金supported by grants from the National Natural Science Foundation of China(U20A2022 and 31871564)the National Key R&D Program of China(2017YFD0300105,2016YFD0300506,and 2017YFD0301700)。
文摘High-yield rice varieties with a suitable growth duration are required for mechanical transplanting in multiple cropping systems. Daily yield is an appropriate criterion for the selection of machine-transplanted rice varieties. The aim of this study was to investigate the growth characteristics and grain production in machine-transplanted medium indica hybrid rice with a high daily yield. We conducted a field experiment on 20 medium indica hybrid rice varieties in 2017 and 2018.Grain yield decreased significantly with growth duration between jointing and heading, but it increased with dry matter accumulation, growth rate between jointing and heading, dry matter partitioning to the stem plus sheath at heading, daily yield, and number of spikelets per panicle. Compared with the medium and low daily yield variety types, the high daily yield variety type increased shoot biomass by improving crop growth rate and dry matter accumulation amount between jointing and heading and after heading. The high daily yield variety type decreased the growth duration pre-heading and the proportions of dry matter partitioned to the leaf lamina at heading and maturity, but it also increased the post-heading accumulated dry matter in the grain and the remobilization of dry matter stored in the vegetative organs. Furthermore,the high daily yield variety type significantly increased the occurrence rate of tillers, which is beneficial for the formation of a larger panicle size and an increase in the grain-filling rate. These changes contributed to a 6.51–23.16% relative increase in grain yield of the high daily yield variety type. In conclusion, the selection of high daily yield indica hybrid rice varieties with shorter pre-heading growth duration, greater tiller occurrence rate and spikelet numbers per panicle, higher post-jointing growth rates and stem plus sheath dry matter accumulation at heading is suitable for machine-transplanted rice.
文摘Nitrogen is one of the most important nutrients in rice production but its uptake dynamics remained relatively unexplored. The present investigation evaluated uptake dynamics over the growing season at different levels of nitrogen fertilizer application. The experiment was conducted during Boro season (November-April) at Bangladesh Rice Research Institute experimental farm, Gazipur, Bangladesh. The experiment involved two modem rice varieties-BRRl dhan28 and BRRI dhan29 and six N rates: 0, 50, 100, 150, 200 and 250 kg·ha^-1. The N uptake pattern was determined at every 15 days from transplanting to maturity. At 150 kg·N·ha^-1, initially N uptake was 0.1 kg.hal.day1 which increased to 0.2 in BRRI dhan28 and 0.4 in BRRI dhan29, respectively. During 30 to 45 DAT, per day N uptake was 2.0 kg-ha1 in BRRI dhan28 and 2.2 in BRRI dhan29 which increased to the peak at 2.4 and 2.8 kg·ha^-1·day^-1 in BRRI dhan28 and BRRI dhan29, respectively, during 45 to 60 DAT. The grain yield showed a stronger correlation with N uptake during 45 to 60 DAT in both the varieties. The highest N uptake contributed to the highest dry matter production in both the varieties.
基金supported by the Special Fund for Agro-Scientific Research in the Public Interest, China (201203031)the China Agriculture Research System (CARS-02-26)
文摘Applying mathematic models to evaluate absorbed-N effects on dry matter production at different developmental stages would help determine proper nitrogen management according to crop demands and yield target. Two field trials were carried out for establishing absorbed-N effects on dry matter production(ANEDr) model, using uniform design in 2010–2011and 2012–2013 winter wheat growing seasons in Hebei Province, China. Another field trial was carried out in 2010–2011for model validation. Dry matter and N concentration in leaf and non-leaf organs were measured at setting, jointing, anthesis, and maturity. Theory of best linear unbiased prediction(BLUP) was applied to analyse the N effects of leaf and non-leaf organs on dry matter production. Within ANEDr model, four N-affected phases at each stage were concerned,leaf absorbed-N effect before this stage, non-leaf organ absorbed-N effect before this stage,leaf absorbed-N effect at this stage, and non-leaf organ absorbed-N effect at this stage. In addition, developmental processes, genotype characters and temperature were three factors that determine each N effect. It was demonstrated that ANEDr model can precisely quantify absorbed-N effects on dry matter production with high correlation coefficient(r=0.95). Comparing with other models, ANEDr model considered both leaf and non-leaf organs according to developmental processes of winter wheat, showed higher flexibility and simplicity, thus could be applied to different environments, cultivars and crops after parameter adjustment.
文摘We studied the characteristics of dry matterproduction and matter partitioning in hybridrice and the relationships of them with heterot-ic effect in 1993. Two popular indica hybrids, Shanyou 63(Zhenshan 97A/Minhui 63 ) and Teyou 63(Longtepu A/Minhui 63), as well as theircommon restorer line, Minhui 63 (elite cultivar
基金Meat and Livestock Australia,Grant/Award Number:P.PSH.1048。
文摘Background:The ability to finish livestock on pasture over the summer–autumn period could improve the profitability of red meat enterprises in drought-prone temperate regions.In south-eastern Australia,traditional perennial options are limited by poor warm-season performance(phalaris,Phalaris aquatica L.)and widespread environmental constraints(lucerne,Medicago sativa L.).We aimed to identify perennial species suitable for summer–autumn finishing.Methods:We tested pure swards of summer-active perennial grasses and herbs(20 cultivars across 14 species)in replicated small-plot experiments at two sites on the Southern Tablelands of New South Wales,Australia.We assessed early persistence,productivity and warm-season nutritive characteristics over 2–3 years.Results:Lucerne and chicory(Cichorium intybus L.)persisted well through drought and produced herbage of high quantity and quality through summer–autumn.Digit grass(Digitaria eriantha Steud.)was highly persistent and productive but nutritive values were generally poor.Cocksfoot(Dactylis glomerata L.),tall fescue(Festuca arundinacea Schreb.),perennial ryegrass(Lolium perenne L.),prairie grass(Bromus willdenowii Kunth.)and plantain(Plantago lanceolata L.)were productive but less persistent through drought,while nutritive values were sometimes inadequate.Conclusions:Chicory is a good alternative to lucerne,given its excellent summer–autumn performance,ability to survive droughts and superior acid soil tolerance.If appropriate management resolves issues with persistence and nutritive value,several of the other species could also be used to close the warm-season feed gap in drought-prone temperate environments.
基金Supported by the Government of Spain(No.CTM2005-05922)
文摘Large quantities of mussel shells (66000-94000 t year^-1), an alkaline material that can be used as a soil amendment, are generated as waste in Galicia, NW Spain. A field trial was carried out by planting different pasture species in a Haplic Umbrisol using a randomized block design with four blocks and six treatments (not amended control or soil amended with lime, finely ground shell, coarsely ground shell, finely ground calcined shell or coarsely ground calcined shell) to compare the effects of lime and mussel shells additions on a soil with a low cation exchange capacity and high AI saturation. The trial was established in March 2007, and samples of plants and soil were collected when plots were harvested in summer 2008 (separating the bulk and rhizosphere soil). The soils were analyzed for pH, total C, total N, available P, exchangeable cations, effective cation exchange capacity and available micronutrients. Dry matter yield was measured in all plots and plants were analyzed for nutrients. Application of mussel shells and the commercial lime resulted in an increase in pH and exchangeable Ca and a decrease in exchangeable Al and Al were most noticeable in the rhizosphere. The amendment of Ca in the plant. saturation. The stability of pH over time was high. These effects also had a positive effect on dry matter yield and concentration
基金Publication of this paper is supported by the National Natural Science Foundation of China (30424813) and Science Publication Foundation of the Chinese Academy of Sciences.
文摘The effects of 0, 2.5, 5.0, and 10.0 pmol/L Cd^2+(Cd(NO3)2.4H2O) and 0, 10, 25, 50, and 100 mmol/L NaCl on growth, photosynthesis and the content of some ions in maize (Zea mays L.) were investigated in the present study. With Increasing concentrations of Cd^2+ or NaCI alone in Hoagland nutrient solution, the chlorophylls and starch content decreased. Combination treatment with salinity and cadmium increased the negative effects observed following the two stresses alone. Plants exhibiting growth retardation in response to one mild stress factor (25-50 mmol/L NaCl) became more tolerant to the other stress factor (Cd). The exposure of plants to cadmium caused a partial reversal of the effects of salinity. Root and shoot growth, ion accumulation and levels of photosynthetic pigments were improved at moderate concentrations of the two stress factors Imposed jointly.